Noninvasive physiological analysis using excitation-sensor modules and related devices and methods

ABSTRACT

Methods and apparatus for qualifying and quantifying excitation-dependent physiological information extracted from wearable sensors in the midst of interference from unwanted sources are provided. An organism is interrogated with at least one excitation energy, energy response signals from two or more distinct physiological regions are sensed, and these signals are processed to generate an extracted signal. The extracted signal is compared with a physiological model to qualify and/or quantify a physiological property. Additionally, important physiological information can be qualified and quantified by comparing the excitation wavelength-dependent response, measured via wearable sensors, with a physiological model.

RELATED APPLICATION

This application claims the benefit of and priority to U.S. ProvisionalPatent Application No. 61/000,181, filed Oct. 25, 2007, the disclosureof which is incorporated herein by reference as if set forth in itsentirety.

FIELD OF THE INVENTION

The present invention relates generally to health and, moreparticularly, to health monitoring.

BACKGROUND OF THE INVENTION

Noninvasive qualification and quantification of physiological propertiesvia wearable sensors may be executed by exciting a physiological regionwith energy and monitoring the response to that energy with one or moresensors. In wearable pulse oximetry, for example, optical energy fromone or more light-emitting diodes (LEDs) excites a region of the bodyrich with blood vessels (such as a finger tip), and a photodiode sensesscattered optical energy relating to blood flow through these bloodvessels. Physiological information extracted via such wearable sensordevices may be confounded by a variety of unavoidable factors. Firstly,the extraction of important physiological information may be obscured byunwanted motion artifacts. These motion artifacts may generate falsesignals that distort physiological information extracted from thewearable sensors. Secondly, the physiological information of interestmay be overpowered by unwanted information from neighboringphysiological features. For example, pulse oximetry data regarding bloodoxygen levels in a blood vessel may be distorted by optical scatter fromthe skin or blood vessels themselves. Other factors may also confoundthe physiological information of interest.

SUMMARY

In view of the above discussion, methods and apparatus for qualifyingand quantifying excitation-dependent physiological information extractedfrom wearable sensors in the midst of interference from unwanted sourcesare provided. According to some embodiments of the present invention, anorganism is interrogated with at least one excitation energy, energyresponse signals from two or more distinct physiological regions aresensed, and these signals are processed to generate an extracted signal.The extracted signal is compared with a physiological model to qualifyand/or quantify a physiological property. Additionally, importantphysiological information can be qualified and quantified by comparingthe excitation wavelength-dependent response, measured via wearablesensors, with a physiological model.

According to some embodiments of the present invention, a method ofmonitoring at least one physiological property (e.g., propertiesassociated with the skin, blood, and/or blood vessels, etc.) of anorganism includes directing energy at a target region of the organism;detecting an energy response signal from the target region and an energyresponse signal from a region adjacent to the target region; processingthe detected signals to produce an extracted energy response signal; andcomparing the extracted energy response signal with a physiologicalmodel to assess a physiological condition of the organism. Energydirected at a target region may include electromagnetic radiation,mechanical energy, acoustical energy, electrical energy, and/or thermalenergy.

Processing the detected signals to produce an extracted energy responsesignal may include subtracting the energy response signal from theregion adjacent to the target region from the energy response signalfrom the target region. In some embodiments, the energy response signalfrom the target region and the energy response signal from a regionadjacent to the target region may be differentially amplified prior toprocessing. In some embodiments, the extracted energy response signalmay be amplified prior to comparing the extracted signal with aphysiological model. The extracted energy response signal may betransmitted (e.g., wirelessly, etc.) to a remote device, such as acomputing device, communication device, entertainment device, etc.

According to some embodiments of the present invention, directing energyat a target region of the organism includes directing electromagneticradiation via one or more optical emitters, such as laser diodes (LDs),light-emitting diodes (LEDs), organic light-emitting diodes (OLEDs),etc. In some embodiments, one or more arrays of optical emitters may beutilized to direct energy at a target region. Monolithic and partiallymonolithic arrays may be utilized. In some embodiments, optical emittersmay be configured to direct electromagnetic radiation at differentwavelengths, and the detectors may be configured to detectelectromagnetic radiation at different wavelengths.

According to some embodiments of the present invention, detecting anenergy response signal from the target region and an energy responsesignal from a region adjacent to the target region includes detectingvia one or more detectors, such as acoustic detectors, auscultatorydetectors, motion detectors, optical detectors, thermal detectors,piezoelectric detectors, etc. In some embodiments, one or more arrays ofdetectors can be utilized.

According to some embodiments of the present invention, an apparatusthat monitors at least one physiological property of an organismincludes at least one energy emitter configured to direct energy at atarget region of the organism; at least one detector configured todetect an energy response signal from the target region and an energyresponse signal from a region adjacent to the target region; and aprocessor. The processor is configured to process the detected signalsto produce an extracted energy response signal, and to compare theextracted energy response signal with a physiological model to assess aphysiological condition (e.g., skin properties, blood flow properties,blood pressure, blood vessel properties, etc.) of the organism. Theprocessor is configured to subtract the energy response signal from theregion adjacent to the target region from the energy response signalfrom the target region to produce an extracted energy response signal.In some embodiments, the processor differentially amplifies the energyresponse signal from the target region and the energy response signalfrom a region adjacent to the target region prior to producing theextracted energy response signal. In some embodiments, the processoramplifies the extracted energy response signal prior to comparing theextracted energy response signal with a physiological model to assess aphysiological condition of the organism.

Energy emitters that direct electromagnetic radiation, mechanicalenergy, acoustical energy, electrical energy, and/or thermal energy maybe utilized. In some embodiments, the at least one energy emittercomprises one or more optical emitters, such as LDs, LEDs, OLEDs, etc.In some embodiments, at least one array of optical emitters are utilizedto direct energy at a target region. Monolithic and partially monolithicarrays may be utilized. In some embodiments, optical emitters may beconfigured to direct electromagnetic radiation at different wavelengths,and the detectors may be configured to detect electromagnetic radiationat different wavelengths.

Detectors utilized to detect an energy response signal from the targetregion and an energy response signal from a region adjacent to thetarget region may include auscultatory detectors, motion detectors,optical detectors, thermal detectors, piezoelectric detectors, etc. Insome embodiments, one or more arrays of detectors can be utilized. Insome embodiments, one or more detectors are utilized to detect an energyresponse signal from the target region and one or more other detectorsare utilized to detect an energy response signal from a region adjacentto the target region. For example, at least one array of detectors maybe utilized to detect an energy response signal from the target regionand at least one array of detectors may be utilized to detect an energyresponse signal from a region adjacent to the target region.

Apparatus according to some embodiments of the present invention mayinclude a transmitter in communication with the processor that isconfigured to transmit (e.g., wirelessly, etc.) the extracted energyresponse signal to a remote computing device, communication device,and/or entertainment device.

According to other embodiments of the present invention, wearableapparatus for monitoring at least one physiological property of anorganism are provided. For example, a wearable apparatus includes ahousing configured to be worn by the organism; at least one energyemitter attached to the housing that is configured to direct energy at atarget region of the organism; at least one detector attached to thehousing that is configured to detect an energy response signal from thetarget region and an energy response signal from a region adjacent tothe target region; and a processor attached to the housing. Theprocessor is in communication with the at least one detector and isconfigured to process detected signals to produce an extracted energyresponse signal, and to compare the extracted energy response signalwith a physiological model to assess a physiological condition of theorganism. In some embodiments, the wearable apparatus is an earpiecethat is configured to be attached to an ear of the organism.

According to other embodiments of the present invention, an apparatusthat monitors at least one physiological property of an organismincludes a processor, and one or more optical emitters configured todirect electromagnetic radiation at a target region of the organism. Theoptical emitters are configured to be electrically biased by theprocessor so as to detect an energy response signal from the targetregion and an energy response signal from a region adjacent to thetarget region. The processor is configured to process the detectedsignals to produce an extracted energy response signal, and to comparethe extracted energy response signal with a physiological model toassess a physiological condition of the organism.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a device for noninvasively monitoring aphysical property of an organism, according to some embodiments of thepresent invention.

FIG. 2 illustrates the excitation-sensor module of FIG. 1 aligned over aphysiological region of interest.

FIG. 3 illustrates an excitation-sensor module comprising a monolithicarray of optical emitters operating as emitters or detectors dependingon the electrical bias, according to some embodiments of the presentinvention.

FIG. 4 illustrates an excitation-sensor module comprising an array ofpiezoelectric sensors operating as both mechanical energy generators aswell as mechanical energy sensors depending on the electrical bias,according to some embodiments of the present invention.

FIGS. 5A-5B illustrate flexible piezoelectric arrays that may beutilized in accordance with embodiments of the present invention.

FIG. 6 illustrates an excitation-sensor array, accord to someembodiments of the present invention, being used to qualify and/orquantify physiological properties of a blood vessel and/or blood, suchas blood pressure or metabolic status of the blood.

FIG. 7 is a graph that illustrates the spectral reflectance response ofmelanin, bilirubin, and hemoglobin.

FIG. 8A is a top plan view of a device for exciting at least one regionwith multiple wavelengths of electromagnetic radiation and sensing theresponse related to each wavelength for comparison with a physiologicalmodel, according to some embodiments of the present invention.

FIG. 8B is side elevation view of the device of FIG. 8A, taken alonglines 8B-8B.

FIG. 9 is a graph that illustrates the spectral extinction coefficientof various forms of hemoglobin.

FIG. 10 is a block diagram of a wearable telemetric device, according tosome embodiments of the present invention.

FIG. 11 is an exploded perspective view of a telemetric hands-free audioheadset capable of both telemetric personal communicationsand/or/entertainment and physiological monitoring, that can be utilizedto implement various embodiments of the present invention.

FIG. 12 illustrates the anatomy of the human ear.

FIG. 13 illustrates the hands-free headset of FIG. 11 being worn by aperson.

DETAILED DESCRIPTION

The present invention now is described more fully hereinafter withreference to the accompanying drawings, in which preferred embodimentsof the invention are shown. This invention may, however, be embodied inmany different forms and should not be construed as limited to theembodiments set forth herein; rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art.

Like numbers refer to like elements throughout. In the figures, thethickness of certain lines, layers, components, elements or features maybe exaggerated for clarity.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof. As used herein, the term “and/or”includes any and all combinations of one or more of the associatedlisted items.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this invention belongs. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the specification andrelevant art and should not be interpreted in an idealized or overlyformal sense unless expressly so defined herein. Well-known functions orconstructions may not be described in detail for brevity and/or clarity.

It will be understood that when an element is referred to as being “on”,“attached” to, “connected” to, “coupled” with, “contacting”, etc.,another element, it can be directly on, attached to, connected to,coupled with or contacting the other element or intervening elements mayalso be present. In contrast, when an element is referred to as being,for example, “directly on”, “directly attached” to, “directly connected”to, “directly coupled” with or “directly contacting” another element,there are no intervening elements present. It will also be appreciatedby those of skill in the art that references to a structure or featurethat is disposed “adjacent” another feature may have portions thatoverlap or underlie the adjacent feature.

Spatially relative terms, such as “under”, “below”, “lower”, “over”,“upper” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is inverted, elements described as “under” or “beneath” otherelements or features would then be oriented “over” the other elements orfeatures. Thus, the exemplary term “under” can encompass both anorientation of “over” and “under”. The device may be otherwise oriented(rotated 90 degrees or at other orientations) and the spatially relativedescriptors used herein interpreted accordingly. Similarly, the terms“upwardly”, “downwardly”, “vertical”, “horizontal” and the like are usedherein for the purpose of explanation only unless specifically indicatedotherwise.

The term “monitoring” refers to the act of measuring, quantifying,qualifying, estimating, sensing, calculating, interpolating,extrapolating, inferring, deducing, or any combination of these actions.More generally, “monitoring” refers to a way of getting information viaone or more sensing elements. For example, “blood health monitoring”includes monitoring blood gas levels, blood hydration, andmetabolite/electrolyte levels.

The term “physiological” refers to matter or energy of or from the bodyof a creature (e.g., humans, animals, etc.). In embodiments of thepresent invention, the term “physiological” is intended to be usedbroadly, covering both physical and psychological matter and energy ofor from the body of an organism. However, in some cases, the term“psychological” is called-out separately to emphasize aspects ofphysiology that are more closely tied to conscious or subconscious brainactivity rather than the activity of other organs, tissues, or cells.

The term “body” refers to the body of a person (or animal) that mayutilize an earpiece module according to embodiments of the presentinvention. Monitoring apparatus, according to embodiments of the presentinvention may be worn by humans and animals.

Referring to FIG. 1, methods and apparatus for qualifying andquantifying one or more physiological properties of an organism,according to some embodiments of the present invention, are illustrated.An extracted signal indicative of the physiological energy response fromtwo or more distinct regions of an organism is generated following theexcitation of at least one region via one or more forms of excitationenergy. In the illustrated embodiment, an excitation-sensor module 101is configured to generate and direct excitation energy towards at leastone surface 120 of an organism and to sense the energy response from atleast two distinct regions of the surface 120. The signal from theexcitation-source module may be passed to a signal extractor 102 forprocessing and/or subtracting the signals to generate at least oneextracted signal more closely related to a physiological property ofinterest. This extracted signal may then be sent to a transmitter 104for wirelessly transmitting the desired information 106 to anotherdevice or network and/or to a signal processor 105 for processing theextracted signal, comparing the processed extracted signal with at leastone physiological model, and sending a physiological assessment to thetransmitter 104.

The excitation-sensor module 101 may include of one or more excitationsource(s) 110, 112, having similar or different excitation elementsand/or excitation configurations, as well as one more sensor element(s)111 having similar or different sensor elements and/or sensorconfigurations. These is elements (110, 112, and 111) are positioned incontact with, or near to, a surface 120 of an organism. The excitationsource(s) 110, 112 can generate energy such as, but not limited to,electromagnetic radiation, mechanical energy, acoustical energy,electrical energy, and/or thermal energy, etc. The sensors 111 candetect one or more of these types of energy.

In some embodiments, an excitation source is a solid-state source, suchas a light-emitting diode (LED), laser diode (LD), lamp, radio ormicrowave transmitter, etc. In some embodiments, a sensor is anacoustic/auscultatory sensor, motion sensor, optical sensor, thermalsensor, etc.

In some embodiments, the excitation sources and sensors are integratedinto a wearable device. This wearable device can be configured toprocess information from the sensors and send processed informationtelemetrically to another device or network. This other device may be aportable device such as a mobile phone, portable computer, portableentertainment device, embedded computer, or the like. The wearabledevice may also include at least one communication module forcommunicating information to the organism and/or entertaining theorganism.

FIG. 2 illustrates an excitation-sensor module 101 positionednoninvasively over the surface 120 (i.e., the skin) of an organism suchthat an optical emitter 212 is positioned over an area largely coveringor completely covering a blood vessel and an optical emitter 210 ispositioned over an area near, but not covering, the blood vessel.Optical detectors 211 are arranged to detect scattered excitation lightfrom two separate regions and generate at least two separate electricalsignals. Signals related to light scattered from the region lacking ablood vessel can be subtracted from signals related to light scatteredfrom the region covering a blood vessel (e.g., via an electroniccircuit). These signals can be subtracted in raw analog form throughanalog mixers, and these signals can also be digitized first andsubtracted in digital form. Regardless, the extracted signal contains“cleaner” information about scattered light coming from the blood vesselitself as compared to light scattered by the blood vessel andneighboring skin tissue. Similarly, as the excitation-sensor module 101is physically one unit, the effects of motion artifacts can also besubtracted because changes in scattered light at each region willtypically happen in unison.

The term “blood vessel”, as used herein refers to veins, arteries,capillaries, and the like.

The optical emitters 210, 212 and optical detectors 211 can be solidstate devices. For example, the optical emitters 210, 212 can include,but are not limited to, a light-emitting diode (LED), a laser diode(LD), a miniature incandescent lamp, a miniature mercury lamp, a lightguide delivering light from an outside source (such as the sun or otherlight source), a multiwavelength source, a microplasma source, an arcsource, a combination of these sources, and the like. Special variantsof light-emitting diodes, such as resonant-cavity light emitting diodes(RCLEDs), superluminescent LEDs (SLEDs), organic LEDs (OLEDs), and thelike can also be utilized. The optical detectors include, but are notlimited to, photodiodes (PDs), avalanche photodiodes (APDs),photomultipliers, or other compact optical detectors.

Though only two optical emitters and optical detectors are shown in FIG.2, it should be understood that multiple optical emitters and opticaldetectors can be arranged in an array. The greater the number of opticalemitters and detectors in an array, the higher resolution ofphysiological features and properties that can be extracted. Forexample, the intensity of optical scatter from a blood vessel atmultiple points along the surface of skin covering that blood vessel canbe used to judge the size of that blood vessel, without having tocalibrate a single optical source for each blood vessel. Unfortunately,increasing the number of optical arrays can increase the fabricationcosts of an optical module 101. Additionally, it can become difficult toalign and package individual optical sources and detectors on a modulefor quantifying the size of a blood vessel.

One methodology for reducing the cost and complexity of a high-densityoptical array is to incorporate a monolithic solid state optical array,such as an LED or LD array. A key benefit of such an array is that solidstate optical emitters can alternately operate as optical emitters oroptical detectors depending on the electrical biasing. Because thesedevices can be fabricated monolithically down to the limits ofstate-of-the-art lithography, a highly dense array of individuallycontrolled LED mesas can be fabricated in a single wafer fabricationrun. Thus, an array of optical emitters/detectors can be fabricatedself-aligned without needing separate packaging techniques. With such adense array, the optical emitters can be alternately biased forward andreverse to operate as optical emitters and detectors respectively. Forexample, for neighboring LED mesas, one LED mesa can be forward-biasedto generate light whereas a neighboring LED mesa can be reverse-biasedto detect light. When the monolithic array is in proximity to thesurface of an organism, the number of mesas detecting significantoptical scatter related to a blood vessel can then be used gauge thesize of that blood vessel. Similarly, the intensity of optical scatterat each mesa can be used to gauge the size of that blood vessel.

FIG. 3 illustrates an exemplary monolithic optical emitter array 312containing individually controlled optical emitters 313 which can alsobe biased as optical detectors. Though a variety of techniques can beused to control the bias through each mesa, one technique is to bond themetal contacts of each individual mesa to a mounting package 314 havingmetal bumps aligned to the monolithic array 313 and having circuitry forcontrolling each individual mesa separately. This packaging forms amodule 300 with the array. FIG. 6 shows how an excitation-sensor arraymodule 612, such as a monolithic optical emitter array module 300, maybe aligned to a blood vessel 620 for gauging the size or shape of theblood vessel, as well as extracting a cleaner signal relatingphysiological information about the blood vessel 620.

The fabrication of solid-state monolithic optical arrays is well knownto those skilled in the art. Solid-state monolithic optical arrays canbe semiconductor optical arrays, such as LED or LD arrays, organic LEDarrays, such as OLEDs and the like. OLED arrays can offer a benefit ofbeing flexed, as shown in FIGS. 5A-5B, at least partially around a bloodvessel. OLEDs can also be dual-based as optical emitters and detectors,but separate optical detectors can also be printed within an array. Theprint-style manufacturing technique for fabricating organic electronicsmakes the manufacture of organic/polymer device arrays potentially lesscostly and tedious than that of traditional LED arrays. Because of theability to “print” device components for organic electronics, OLEDarrays, organic photodetector arrays, and organic piezoelectric arrayscan be deposited in the same module and interlaced in the same array.This adds higher-level physiological sensing functionality by increasingthe number of physiological-related parameters that can be monitored atthe same time.

Piezoelectric arrays can also be employed for noninvasively monitoringthe physiological properties of an organism, according to someembodiments of the present invention. This allows mechanical energy fromsome piezoelectric elements to couple with a region of the organismwhile other piezoelectric elements measure the response. The processingof this information to generate information on physiological dimensionsor physiological properties can be the same as that described formonolithic LED arrays 312.

Many polar semiconductors contain piezoelectric properties, and thusseveral types of device arrays on several types of semiconductors can beused as piezoelectric sensors and/or actuators, according to embodimentsof the present invention. For example, metal arsenides and metalnitrides, such as aluminum indium gallium arsenide or aluminum indiumgallium nitride alloys, and the like, can be used to fabricatepiezoelectric arrays. The elements of these arrays can bemicro-manufactured or nano-manufactured as cantilevers, membranes,flexible rods, or the like using standard microelectromechanical systems(MEMS) and nanoelectromechanical (NEMS) fabrication techniques.Similarly, simple device structures such as field effect transistors,resistors, and even light-emitting diodes can be operated aspiezoelectric sensors. Thus, an LED array can be used as both an opticalemitter-detector array or piezoelectric sensing array depending on thebiasing of the array. Methods of fabricating piezoelectric arrays arewell known to those skilled in the art. The monolithic piezoelectricactuator-sensor array 400 of FIG. 4 can be fabricated as an array 412 ofmetallic contacts 413 on a semiconductor surface, where the surface mayor may not be defined into individual mesas. The packaging module 414can be employed in the same manner as package 314 of FIG. 3.

As described earlier, flexible organic/polymer arrays can also beemployed for physiological monitoring as shown in FIG. 6. The arrayelements (e.g., 513, FIG. 5A) can come from any number of opticalemitting (OLED), optical detecting (OLED or organic photodetector),piezoelectric (such as polarized fluoropolymers), or other sensingelements. A secondary screen-printed (or similar) film 523 (FIG. 5B),which may be deposited on the organic polymer array layer 512 or on aseparate layer 522, can be used to electrically access each deviceelement 513. In the case of a polymer piezoelectric array 500, polarizedpolymers, such as polyvinylidene fluoride (PVDF), can be used as anactive piezoelectric element for generating and/or sensing mechanicalenergy is from an organism. For example, by generating mechanical energywith one filament in the array and detecting the mechanical energyresponse coming from the organism at other filaments, a physiologicalmap of a feature, such as a blood vessel, can be processed. This can beused to gauge the size of a blood vessel opening and closing in time.

Embodiments of the present invention can be used to assess bloodpressure or blood pressure properties in a blood vessel. For example,the information on the size of a blood vessel, as well as the change insize of a blood vessel during blood flow, can be combined withinformation regarding the total flow of blood to assess blood pressure.Namely, the size and change of size in a blood vessel can relate thearea of a blood vessel, and this can be combined with the volumetricflow rate of blood to gauge or estimate blood pressure.

Referring to FIG. 6, reflective pulse oximetry can be combined withblood vessel size estimation via optical scatter detection, according tosome embodiments of the present invention. For example, an opticalemitter generating blue light can be used to generate an optical scattersignal more closely related to the size of a blood vessel, shown by Δyin FIG. 6. An optical emitter generating IR light can be used togenerate an optical scatter signal more closely related to the bloodflow in the blood vessel, shown by 630 in FIG. 6. A third and fourthoptical emitter, violet and red respectively, may be located near (butnot covering) the blood vessel, for example in an arrangement as thatillustrated in FIG. 2. Optical scatter signals from these sources aremore closely related to optical scatter from the skin or other tissue.Thus, when these skin-related optical scatter signals are differentiallyamplified with respect to their blood-vessel-related counterparts, atleast two extracted signals can be generated that are more closelyrelated to the size of a blood vessel and the blood flow rate through ablood vessel. These extracted signals can then be digitized, processed,and compared with a physiological model related to blood pressure toqualify and quantify blood pressure in real time.

The aforementioned IR scatter signal more closely related to the bloodflow in the blood vessel may also contain some information related tothe optical scatter from the expanding blood vessel wall. Thus,differentially amplifying the aforementioned blue scatter signal moreclosely related to the size of a blood vessel with respect to theaforementioned IR scatter signal can help subtract artifacts associatedwith expanding blood vessel size from the desired blood flowinformation. Thus, second order affects can be alleviated, to at leastsome degree, from the overall assessment of blood pressure.

Embodiments of the present invention can be utilized for qualifying andquantifying a variety of physiological properties in physiologicaltissue and fluids. For example, the optical scatter signal associatedwith blood glucose in a blood vessel can be more accurately and/orprecisely extracted. In another embodiment, blood hemoglobin components,such as oxyhemoglobin, methemoglobin, carboxyhemoglobin, and the like,can be more accurately and/or precisely extracted. In these embodiments,the optical scatter response associated with the skin is subtracted fromthe optical scatter response associated with skin+blood metabolites togenerate a clean extracted signal more closely related to bloodmetabolite quality and quantity. In each case, the optical signalassociated with scatter from the skin tissue is separated from theoptical signal associated with the blood vessel or blood components.This embodiment utilizes multiple emitters, multiple detectors, or both,with each emitter and detector located in a distinct region in thevicinity of a blood vessel—either directly over the blood vessel or nearbut not covering the blood vessel. If the optical emitters and detectorsare located too far apart from the region of interest, it can bedifficult to extract the desired physiological-related signal. This isbecause optical scatter from separate areas can be too dissimilar forsuccessful differential amplification and extraction of a clearphysiologically related signal.

In some embodiments of the present invention, the same sensors, sensorconfigurations, and processing, can be used to extract signals relatedto the physiological properties of the skin. For example, informationrelated to the size of a blood vessel or flow of blood through a bloodvessel can be subtracted from an optical scatter signal reflected fromthe skin. This will yield cleaner information more closely related tothe physiological properties of the skin, such as skin metabolitelevels, hydration, elasticity, and the like.

As described above, the scatter intensity of light for each wavelengthof electromagnetic excitation can be used to qualify and/or quantify aparticular physiological parameter. For example, in humans, shorterwavelength optical radiation (blue-UV) reflects largely from the skin,whereas longer wavelength radiation (red-IR) can penetrate through bloodvessels (FIG. 7). Thus, an approach for qualifying and/or quantifying atleast one physiological property of an organism according to someembodiments of the present invention is to generate at least twoextracted signals, each indicative of at least one physiological energyresponse from at least one region of the organism following theelectromagnetic excitation of at least one region with at least twowavelengths of electromagnetic excitation. The wavelength-dependentenergy response from each region can then be sensed by at least oneneighboring sensor and/or sensor array and converted into at least twoelectrical signals. This energy response can be mechanical,acoustical/auscultatory, electrical, or thermal in origin. The two ormore electrical signals can be converted into extracted signals byfiltering out each signal with respect to noise, as described earlier.These extracted signals are each indicative of at least onephysiological energy response to at least one wavelength ofelectromagnetic energy. These extracted signals can then be amplified,compared, processed, and compared with at least one physiological modelto qualify and/or quantify at least one physiological property of theorganism. One specific example of physiological properties that can beextracted, such as blood metabolites, is shown in FIG. 9.

A specific embodiment of noninvasively qualifying and/or quantifying aparticular physiological parameter is shown in FIGS. 8A-8B. In thisembodiment, the electromagnetic excitation sources, 810, 812, areoptical emitters. Optical emitter 810 generates long wavelengthradiation and optical emitter 812 generates short wavelength radiation.The optical detector 811 converts the optical scatter from the opticalemitters 810, 812 into an electrical signal. The short wavelengthoptical emitter 812 generates optical radiation which is reflected fromthe surface of the blood vessel 820, whereas the long wavelength opticalemitter 810 generates optical radiation which is at least partiallyreflected from the blood inside the blood vessel. If the opticalemitters 810, 812 are pulsed and synchronized in time with the opticaldetector 811, at least two separate signals can be extracted for eachexcitation wavelength. For example, the electrical signal associatedwith the short wavelength optical energy from the optical source 812 ismore closely associated with the size of the blood vessel 820, whereasthe electrical signal associated with the long wavelength optical energyfrom the optical source 810 is more closely associated with the bloodflow through the blood vessel. Thus, as described earlier, by comparingthese independent signals, an assessment of blood pressure can beestimated.

Embodiments of the present invention described herein can be quiteuseful when integrated into a wearable device, such as a wearabletelemetric device. In some embodiments, a wearable device cancommunicate telemetrically with a portable computer or portablecommunication device, such as a cellular phone, personal digitalassistant, or the like. Thus, a person wearing the device can view areal-time assessment of personal vital signs through a portable viewscreen. In some embodiments, this telemetric information can betransmitted through a cellular network and onto the world-wide-web forstorage in a database. This stored data can then be accessed through theweb. Devices according to embodiments of the present invention can becomprised of compact, low-power solid-state devices, such as LEDs,photodiodes, piezoelectric elements, microphones, NEMS/MEMS devices, orthe like. As such, embodiments of the present invention can beintegrated into wearable monitors.

FIG. 10 illustrates the use of excitation-sensor modules 1012 in awearable physiological monitor 1000. The modules 1012 can be integratedinto a flexible circuit board or flexible connector, connected to aBluetooth processing board. Flexible circuit boards are typicallyfabricated from a polymer with integrated copper electrodes and circuitpaths.

In a particular embodiment, the wearable physiological monitor 1000 canbe integrated into the main body 1205 of a telemetric earpiece, as shownin FIG. 11. FIG. 11 illustrates details about the location of sensors incertain parts of an earpiece module 1205, according to embodiments ofthe present invention. The ear support 1201 contains a pinna (helix)cover 1202 that may contain sensors for monitoring physiological andenvironmental factors. This structure is particularly useful for sensingmethodologies which require energy to be transmitted through the thinlayers of the pinna (the outer ear). Though any portion of the pinna canbe covered and/or contacted, in some embodiments, the pinna cover 1202overlaps at least a part of the helix or a part of the scapha of an ear(FIG. 12 illustrates a human ear). Likewise, an optical absorptiondetector, composed of an optical emitter and optical detector, can beintegrated into the pinna cover 1202 for monitoring, for example,hydration, dosimetry, skin temperature, inductive galvanometry,conductive galvanometry, and the like.

Galvanometry, the measurement of electrical properties of the skin, canbe measured inductively, through contactless electromagnetic inductionwithout contacts, or conductively, with two, three, four, or moreconductivity probes. Additionally, a 4-point conductivity probetechnique, such as that used for measuring the conductivity ofsemiconductor wafers, can be applied. A variety of sensors can beintegrated into the earpiece fitting 1208. For example, a galvanometricdevice can be integrated into the surface 1209 of the earpiece fittingwhere the earpiece fitting touches the skin of the outer ear. Aparticularly strong pulse response can be monitored withexcitation-sensor modules such as those described above mounted in theearpiece fitting region 1209, touching the acoustic meatus (FIG. 12).Additionally, an inductive device, such as an inductive coil 1214, canbe integrated along the earpiece fitting body to measure movements ofthe tympanic membrane inductively. The inductive impedance can also bemeasured with the inductive coil 1214 or another inductive sensor, andthis can be applied towards contactless galvanometry. The inductive coil1214 can include one or more coils arranged in any orientation, and acore material, such as an iron-containing material, may be used toimprove the sensitivity of the response. In some cases, multiple coilsmay be used to facilitate the canceling of stray electromagneticinterference. Sensors can also be integrated into the end tip 1212 ofthe earpiece fitting 1208 to measure physiological properties deeperinto the ear canal. For example, the modules of FIGS. 2-4 and 5A-5B maybe located in, at, or near the end tip region 1212 in a module 1213. Thesensors on the module 1213 in this region are carefully arranged so asnot to prevent the transmission of sound (from the built-incommunication module) and to not be distorted during earpiece placementand removal. The end tip sensor module 1213 can contain several types ofsensors for generating multiple types of energy and detecting multipletypes of energy, and this module can be integrated into the speakermodule (part of the communication module) inside the earpiece fitting1208 that is used for sound transmission to the user during telemetricconversations. In some embodiments, the speaker module can be used as amicrophone to measure auscultatory signals from the body. This may beespecially useful for measuring low frequency signals less than 1000 Hz.Employing the speaker as a microphone may require impedance matching tomaximize the auscultatory signal extraction. The modules of FIGS. 2-4and 5A-5B can be located in, at, or near other parts of the earpiecemodule, such as the earpiece fitting 1208 surface 1209, the ear support1201, or the earpiece body 1205.

Another multifunctional earpiece module 1500, according to embodimentsof the present invention, is illustrated in FIG. 13. The illustratedearpiece module 1500 includes the embodiments illustrated in FIG. 11,such as a pinna cover 1502, an ear support 1501, a mouthpiece 1516, anearpiece body 1505, and the like. Additionally, the earpiece module 1500may contain an extension 1511 with sensors for monitoring jaw motion,arterial blood flow near the neck, or other physiological andenvironmental factors near the jaw and neck region.

The person illustrated in FIG. 15 is also wearing an earring monitor1514 according to embodiments of the present invention. Because at leastone portion of an earring may penetrate the skin, earring monitor 1514may contain sensors and telemetric circuitries that provide access tovarious blood analytes through iontophoresis and electrochemical sensingthat may not be easily accessible by the other portions of the earpiecemodule 1500. Additionally, the earring monitor 1514 may provide a goodelectrical contact for ECG or skin conductivity.

The foregoing is illustrative of the present invention and is not to beconstrued as limiting thereof. Although a few exemplary embodiments ofthis invention have been described, those skilled in the art willreadily appreciate that many modifications are possible in the exemplaryembodiments without materially departing from the teachings andadvantages of this invention. Accordingly, all such modifications areintended to be included within the scope of this invention as defined inthe claims. The invention is defined by the following claims, withequivalents of the claims to be included therein.

1. A method of monitoring at least one physiological property of anorganism, comprising: directing energy at a target region of theorganism and at a region adjacent the target region, wherein the targetregion comprises substantially more blood vessels than the adjacentregion; detecting an energy response signal from the target region andan energy response signal from the adjacent region, wherein thedirecting and detecting steps are performed by a device worn by theorganism; processing the detected signals to produce an extracted energyresponse signal; and comparing the extracted energy response signal witha physiological model to assess a physiological condition of theorganism.
 2. The method of claim 1, wherein directing energy at thetarget region and adjacent region comprises directing electromagneticradiation, mechanical energy, acoustical energy, electrical energy,and/or thermal energy at the target region and adjacent region.
 3. Themethod of claim 1, wherein processing the detected signals to produce anextracted energy response signal comprises subtracting the energyresponse signal from the region adjacent to the target region from theenergy response signal from the target region.
 4. The method of claim 1,further comprising differentially amplifying the energy response signalfrom the target region and the energy response signal from a regionadjacent to the target region prior to the processing step.
 5. Themethod of claim 1, further comprising amplifying the extracted energyresponse signal prior to the comparing step.
 6. The method of claim 1,further comprising transmitting the extracted energy response signal toa remote device.
 7. The method of claim 6, wherein transmitting theextracted energy response signal to a device comprises wirelesslytransmitting the extracted energy response signal.
 8. The method ofclaim 6, wherein the device is selected from the group consisting ofcomputing devices, communication devices, and entertainment devices. 9.The method of claim 1, further comprising transmitting the extractedenergy response signal to the organism.
 10. The method of claim 1,wherein directing energy at the target region and adjacent region of theorganism comprises directing electromagnetic radiation via at least oneoptical emitter.
 11. The method of claim 8, wherein the at least oneoptical emitter is selected from the group consisting of laser diodes(LDs), light-emitting diodes (LEDs), and organic light-emitting diodes(OLEDs).
 12. The method of claim 8, wherein the at least one opticalemitter comprises at least one array of optical emitters.
 13. The methodof claim 1, wherein detecting an energy response signal from the targetregion and an energy response signal from a region adjacent to thetarget region comprises detecting via at least one detector selectedfrom the group consisting of acoustic detectors, auscultatory detectors,motion detectors, optical detectors, thermal detectors, andpiezoelectric detectors.
 14. The method of claim 1, wherein thephysiological condition of the organism includes properties of skin,blood, and/or blood vessels of the organism.
 15. The method of claim 1,wherein the physiological condition of the organism comprises one ormore of the following: blood pressure, volume of blood flow through ablood vessel, and size of at least one blood vessel.
 16. The method ofclaim 1, wherein the target region comprises vascular and non-vasculartissue, and wherein the adjacent region is dominated by non-vasculartissue.
 17. The method of claim 1, wherein directing energy at a targetregion of the organism comprises directing electromagnetic radiation viaat least one optical emitter and wherein detecting energy responsesignals from the target region and region adjacent to the target regioncomprises electrically biasing at least one optical emitter to operateas an optical detector.
 18. The method of claim 12, wherein the at leastone array of optical emitters comprises at least one monolithic array ofoptical emitters.
 19. The method of claim 12, wherein the at least onearray of optical emitters comprises at least one partially monolithicarray of optical emitters.
 20. The method of claim 1, wherein directingenergy at a target region of the organism comprises directingelectromagnetic radiation at different wavelengths.
 21. The method ofclaim 1, wherein detecting an energy response signal from the targetregion and an energy response signal from a region adjacent to thetarget region comprises detecting electromagnetic radiation at differentwavelengths.
 22. The method of claim 21, further comprising measuringblood flow in the organism by detecting electromagnetic radiation at afirst wavelength and measuring motion of the organism by detectingelectromagnetic radiation at a second wavelength that is shorter thanthe first wavelength.
 23. The method of claim 1, wherein processing thedetected signals to produce an extracted signal comprises subtracting asignal associated with motion from a signal associated with aphysiological condition of the organism.
 24. The method of claim 1,wherein the device is a wearable device that comprises a plurality ofemitters and a plurality of detectors.
 25. A method of monitoring atleast one physiological property of an organism, comprising: directingenergy at a target region of the organism, wherein the target region hasa substantial amount of blood vessels; detecting an energy responsesignal from the target region and an energy response signal from aregion adjacent the target region, wherein the adjacent region has asubstantially less amount of blood vessels than the target region,wherein the directing and detecting steps are performed by a device wornby the organism; processing the detected signals to produce an extractedenergy response signal; and comparing the extracted energy responsesignal with a physiological model to assess a physiological condition ofthe organism.
 26. The method of claim 25, wherein directing energy atthe target region comprises directing electromagnetic radiation,mechanical energy, acoustical energy, electrical energy, and/or thermalenergy at the target region.
 27. The method of claim 25, whereinprocessing the detected signals to produce an extracted energy responsesignal comprises subtracting the energy response signal from the regionadjacent to the target region from the energy response signal from thetarget region.
 28. The method of claim 25, further comprising amplifyingthe extracted energy response signal prior to the comparing step. 29.The method of claim 25, further comprising transmitting the extractedenergy response signal to a remote device.
 30. The method of claim 29,wherein transmitting the extracted energy response signal to a devicecomprises wirelessly transmitting the extracted energy response signal.31. The method of claim 30, wherein the device is selected from thegroup consisting of computing devices, communication devices, andentertainment devices.
 32. The method of claim 25, further comprisingtransmitting the extracted energy response signal to the organism. 33.The method of claim 25, wherein directing energy at the target region ofthe organism comprises directing electromagnetic radiation via at leastone optical emitter.
 34. The method of claim 33, wherein the at leastone optical emitter is selected from the group consisting of laserdiodes (LDs), light-emitting diodes (LEDs), and organic light-emittingdiodes (OLEDs).
 35. The method of claim 33, wherein the at least oneoptical emitter comprises at least one array of optical emitters. 36.The method of claim 25, wherein detecting an energy response signal fromthe target region and an energy response signal from a region adjacentto the target region comprises detecting via at least one detectorselected from the group consisting of acoustic detectors, auscultatorydetectors, motion detectors, optical detectors, thermal detectors, andpiezoelectric detectors.
 37. The method of claim 25, wherein thephysiological condition of the organism includes properties of skin,blood, and/or blood vessels of the organism.
 38. The method of claim 25,wherein the physiological condition of the organism comprises one ormore of the following: blood pressure, volume of blood flow through ablood vessel, and size of at least one blood vessel.
 39. The method ofclaim 25, wherein the target region comprises vascular and non-vasculartissue, and wherein the adjacent region is dominated by non-vasculartissue.
 40. The method of claim 25, wherein directing energy at a targetregion of the organism comprises directing electromagnetic radiation viaat least one optical emitter and wherein detecting energy responsesignals from the target region and region adjacent to the target regioncomprises electrically biasing at least one optical emitter to operateas an optical detector.
 41. The method of claim 25, wherein processingthe detected signals to produce an extracted signal comprisessubtracting a signal associated with motion from a signal associatedwith a physiological condition of the organism.
 42. The method of claim25 , wherein the device is a wearable device that comprises a pluralityof emitters and a plurality of detectors.